Hydrogen storage system using hydrogen storage material

ABSTRACT

The present invention relates to a hydrogen storage system using a hydrogen storage material and can increase a heat exchanging efficiency by improving a contact frequency to the heat exchanger by vibrating the heat exchanger that is mounted in the hydrogen storage tank using the hydrogen storage material by using a vibrator to induce resonance vibration of the packed storage material powder.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims under 35 U.S.C. §119(a) priority toKorean Patent Application Number 10-2009-0119066, filed Dec. 3, 2009,the entire contents of which application is incorporated herein for allpurposes by this reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates in general to a hydrogen storage systemfor a vehicle, and more particularly to a hydrogen storage system usinga hydrogen storage material that can largely lower a charging time whena material that reversibly stores/discharges hydrogen is used.

2. Description of Related Art

In general, fuel cell vehicles require hydrogen in an amount of 5 kg ormore in order to travel a distance in one charge.

However, high pressure (35 or 70 MPa) hydrogen storage systems that arecurrently used have limits in their packaging for installation invehicles due to insufficient volume storage density.

Accordingly, a technology using a hydrogen storage material that has ahigh storage density, that is, a hydrogen storage alloy, a chemicalhydrogen material or a porous material has been developed.

In particular, the hydrogen storage alloy or complex metal hydridesaddress the long charging time that is due to excessive physical orchemical reaction heat that is generated when hydrogen is charged(stored), but since the hydrogen storage alloy can reversibly store anddischarge hydrogen and has a high volume storage density in respect tohigh pressure hydrogen, its application to hydrogen storage systems hasbeen investigated.

The hydrogen storage system as described above has been developed suchthat a heat exchanger is inserted into the hydrogen storage system sothat heat is exchanged due to the reaction heat of the hydrogen storagealloy.

However, if the size of the heat exchanger is made larger by increasinga contact area between the storage material and the heat exchanger inorder to improve heat exchanging performance, a hydrogen charging timemay be lowered, but the charging space of the hydrogen storage materialis made narrow.

The information disclosed in this Background of the Invention section isonly for enhancement of understanding of the general background of theinvention and should not be taken as an acknowledgement or any form ofsuggestion that this information forms the prior art that is alreadyknown in this country to a person skilled in the art.

BRIEF SUMMARY OF THE INVENTION

Preferred aspects of the present invention provide a hydrogen storagesystem using a hydrogen storage material, which suitably lowers ahydrogen charging time while the size of the heat exchanger is notsuitably increased by improving heat exchanging performance and byimproving a contact frequency between the heat exchanger and the storagematerial, and suitably prevents the charging space of the hydrogenstorage material from being made small.

Preferred embodiments of the present invention provide a hydrogenstorage system using a hydrogen storage material, that preferablycomprises a heat exchanger that cycles a heat transfer medium in ahydrogen storage tank made with a hydrogen storage alloy, wherein theheat exchanger preferably includes a vibration unit that appliesvibration to the heat transfer medium so that a flow is converted into avortex.

In preferred embodiments, the vibrator is a piezoelectric vibrator.

In further preferred embodiments, the vibration unit is mounted in theheat exchanging tube or in a heat transfer medium chamber that allows aheat transfer medium to flow thereinto.

In other further preferred embodiments, the vibration unit vibrates theheat exchanger by using a resonance frequency of the hydrogen storagematerial.

Preferably, the vibration unit generates a vibration frequency by usinga resonance frequency of the hydrogen storage material regularly or in apredetermined cycle.

According to still further preferred embodiments, the heat exchangerfurther increases a heat exchanging volume by suitably forming a heatexchanging pin so that the heat exchanging volume of the heat exchangingtube that makes a flow path of the heat transfer medium is suitablyincreased and forming a groove that is suitably obtained by modifyingthe heat exchanging tube between the pins.

According to further preferred embodiments of the present invention,since heat exchanging performance is suitably improved, the hydrogencharging time of the hydrogen storage system using the hydrogen storagematerial may be suitably lowered while the size of the heat exchanger isnot increased, such that the packing space of the hydrogen storagematerial is not lost.

Further, according to preferred embodiments, since the present inventionis independently constituted in a known heat exchanger, a chargingperformance of the hydrogen storage system may be suitably increasedwhile a know heat exchanger is not largely modified.

It is understood that the term “vehicle” or “vehicular” or other similarterm as used herein is inclusive of motor vehicles in general such aspassenger automobiles including sports utility vehicles (SUV), buses,trucks, various commercial vehicles, watercraft including a variety ofboats and ships, aircraft, and the like, and includes hybrid vehicles,electric vehicles, plug-in hybrid electric vehicles, hydrogen-poweredvehicles and other alternative fuel vehicles (e.g. fuels derived fromresources other than petroleum).

As referred to herein, a hybrid vehicle is a vehicle that has two ormore sources of power, for example both gasoline-powered andelectric-powered.

The methods and apparatuses of the present invention have other featuresand advantages which will be apparent from or are set forth in moredetail in the accompanying drawings, which are incorporated herein, andthe following Detailed Description of the Invention, which togetherserve to explain certain principles of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features of the present invention will now bedescribed in detail with reference to certain exemplary embodimentsthereof illustrated by the accompanying drawings which are givenhereinafter by way of illustration only, and thus are not limitative ofthe present invention, and wherein:

FIG. 1 is an exemplary configuration view of a hydrogen storage systemusing a hydrogen storage material, which is provided with an internalheat exchanger according to the present invention.

FIGS. 2A and 2B are exemplary configuration views of a heat exchangingtube from which a heat exchanging pin of the internal heat exchanger isremoved according to the present invention.

FIG. 3 is a cross-sectional view of a heat exchanging tube in which aheat exchanging pin of the internal heat exchanger according to thepresent invention is formed.

It should be understood that the appended drawings are not necessarilyto scale, presenting a somewhat simplified representation of variouspreferred features illustrative of the basic principles of theinvention. The specific design features of the present invention asdisclosed herein, including, for example, specific dimensions,orientations, locations, and shapes will be determined in part by theparticular intended application and use environment.

DETAILED DESCRIPTION OF THE INVENTION

As described herein, the present invention includes a hydrogen storagesystem comprising a heat exchanger, a hydrogen storage tank comprised ofa hydrogen storage alloy, and a heat transfer medium, wherein the heatexchanger includes a vibration unit.

In preferred embodiments, the heat transfer medium is cycled by the heatexchanger in the hydrogen storage tank.

In other preferred embodiments, the vibration unit applies vibration tothe heat transfer medium so that a flow is converted into a vortex.

Reference will now be made in detail to various embodiments of thepresent invention(s), examples of which are illustrated in theaccompanying drawings and described below. While the invention(s) willbe described in conjunction with exemplary embodiments, it will beunderstood that present description is not intended to limit theinvention(s) to those exemplary embodiments. On the contrary, theinvention(s) is/are intended to cover not only the exemplaryembodiments, but also various alternatives, modifications, equivalentsand other embodiments, which may be included within the spirit and scopeof the invention as defined by the appended claims.

According to certain preferred embodiments, and as shown in FIG. 1, forexample, FIG. 1 illustrates a configuration view of a hydrogen storagesystem using a hydrogen storage material that is provided with aninternal heat exchanger. According to certain preferred embodiments, thepresent invention preferably includes a vibration unit that largelylowers a hydrogen charging time by suitably improving heat exchangingperformance while the size of an internal heat exchanger 2 of a hydrogenstorage tank 1 using a hydrogen storage alloy is not suitably increased.

According to further preferred embodiments, a heat exchanger 2implements a function that absorbs the internal heat of a hydrogenstorage tank 1 by using a heat exchanging medium and a function thatreceives heat from the heat transfer medium and suitably transfers heatto the hydrogen storage material and a heat exchanging pin 5.

Preferably, a heat exchanger 2 according to the certain preferredembodiments can satisfy both sides between the heat exchanger and thehydrogen charging space.

Accordingly, in preferred exemplary embodiments, the heat exchanger 2 issuitably configured by a heat exchanging tube 3 that is suitablyinserted into a hydrogen storage tank 1 and performs heat exchangethrough the cycling heat transfer medium by the reaction heat of thehydrogen storage alloy, heat exchanging pin 5 that is suitably mountedso as to increase the heat exchanging area of heat exchanging tube 3, achamber 4 that suitably receives the medium after it flows into heatexchanging tube 3 and cycles, and a vibration unit that vibrates theheat transfer medium before it flows into heat exchanging tube 3.

According to further preferred embodiments and as shown in FIG. 2A forexample, FIG. 2A illustrates a heat exchanging tube 3 according topreferred embodiments of the present embodiment.

As shown in the drawing, a heat exchanging tube 3 is suitably configuredby an integral tube that has an inlet 3 a that inflows the heat transfermedium and an outlet 3 b that outflows it cycling therein and suitablydischarges it again at ends thereof, but the tube has a structure thathas a plurality of repetition paths that repeatedly cross the internalspace of a hydrogen storage tank 1 and cycles the heat transfer medium.

Preferably, a heat exchanging tube 3 is a path that inflows the heattransfer medium, and allows the flowing heat transfer medium to besuitably contacted with the hydrogen storage material and heatexchanging pin 5, thereby absorbing the heat.

In other embodiments of the present invention, a heat exchanging tube 3absorbs the internal heat of hydrogen storage tank 1 by the heattransfer medium and receives heat that is suitably provided from theheat transfer medium and suitably transfers heat to the hydrogen storagematerial and heat exchanging pin 5, which is suitably performed byheating.

According to further preferred embodiments, a heat exchanging tube 3 hasvarious cross-sectional shapes so as to suitably increase the heatexchanging efficiency through heat exchanging pin 5.

As an example of the cross section of a heat exchanging tube 3, as shownin FIG. 3, for example, it can be suitably bent and its cross sectioncan be suitably changed by forming the groove along the length directionof heat exchanging tube 3.

Chamber 4 according to further preferred embodiments of the presentinvention, wraps inlet 3 a and outlet 3 b of heat exchanging tube 3 andfixes it, and has a structure in which the heat transfer medium issuitably discharged from the inside thereof to inlet 3 a and flowsthrough outlet 3 b thereinto.

Preferably, to provide the structure of a chamber 4, a valve and thelike is provided, which is suitably the same as the structure that isapplied to implement the same function.

According to further preferred embodiments, a heat exchanging pin 5functions to suitably increase a tube volume by suitably forming it oneach tube that is configured by a heat exchanging tube 3, and preferablyheat exchanging is suitably performed when cooling and heating areconducted by contacting the storage material and heat exchanging tube 3in the internal space of hydrogen storage tank 1.

The vibration unit according to preferred embodiments of the presentinvention implements a function that suitably improves heat exchangeperformance between a heat exchanging tube 3 and a heat transfer mediumby vibrating a heat exchanger 2 while it is attached to the heatexchanger 2, and heat exchanging performance between the heat exchangingpin and the storage material powder.

Preferably, the vibration unit vibrates the hydrogen storage materialthat is contacted with the heat exchanger by vibrating the heatexchanger and increases an effective contact area to the heat exchanger,thereby suitably improving the heat transfer efficiency.

Further, the flow of heat transfer medium is suitably converted into thevortex to double an improvement of heat transfer efficiency.

Accordingly, in further preferred embodiments, the vibration unit issuitably configured by a vibrator 10 that applies vibration to a heatexchanger 2, and the vibrator 10 preferably connects a wire 11 tosuitably provide power, and the power is preferably controlled by usinga separate controller.

According to other further preferred embodiments of the presentinvention, the controller suitably implements controlling that isperformed so that the vibration number of the vibrator 10 suitablycorresponds to the resonance frequency of the storage material powder tofurther increase the heat exchanging performance.

Preferably, the vibrator 10 is mounted in various positions so as toincrease the vibration performance of the heat transfer medium, and apiezoelectric vibrator is suitably applied.

According to certain exemplary embodiments, a vibrator 10 is suitablymounted at a chamber 4 that receives the heat transfer medium, therebyvibrating a heat exchanger 2 and suitably forming the vortex in the flowof heat transfer medium as shown in FIG. 2A.

Alternatively, in other further embodiments of the present invention, avibrator 10, as shown in FIG. 2B, is suitably mounted at a heatexchanging tube 3, thereby vibrating heat exchanger 2.

As described herein, in preferred embodiments of the present invention,a heat exchanging efficiency is improved in the course of cycling theheat transfer medium by an increase in heat exchange area through thegroove shapes of heat exchanging pin 5 and heat exchanging tube 3 in ahydrogen storage tank 1, and the heat exchanging efficiency is furtherimproved by using a change of heat transfer medium flow that cycles toheat a exchanging tube 3 by vibrating the heat transfer medium in apredetermined frequency by using a vibrator 10.

According to preferred embodiments of the present invention, it ispossible to further increase the heat exchanging efficiency by settingthe vibration number that is suitably applied to the heat transfermedium in a vibrator 10 to the resonance frequency of the storagematerial powder to suitably increase the effective contact area betweenthe storage material and heat exchanger 2.

Further, in preferred embodiments, when vibration is suitably appliedthrough a vibrator 10 to the heat transfer medium, if the vibration isapplied in a predetermined cycle while the vibration is not constant, ahigher heat exchanging performance may be generated.

As described herein, in preferred embodiments of the present invention,since the heat exchanging performance efficiency is largely increased byonly a simple function that applies the vibration to the heat transfermedium so that the flow thereof is suitably converted into the vortex,the size of heat exchanger 2 is not suitably increased, such that thehydrogen packing space in a hydrogen storage tank 1 is not lost.

The foregoing descriptions of specific exemplary embodiments of thepresent invention have been presented for purposes of illustration anddescription. They are not intended to be exhaustive or to limit theinvention to the precise forms disclosed, and obviously manymodifications and variations are possible in light of the aboveteachings. The exemplary embodiments were chosen and described in orderto explain certain principles of the invention and their practicalapplication, to thereby enable others skilled in the art to make andutilize various exemplary embodiments of the present invention, as wellas various alternatives and modifications thereof. It is intended thatthe scope of the invention be defined by the Claims appended hereto andtheir equivalents.

1. A hydrogen storage system using a hydrogen storage material,comprising: a heat exchanger that cycles a heat transfer medium in ahydrogen storage tank made with a hydrogen storage alloy, wherein theheat exchanger includes a vibration unit that applies vibration to theheat transfer medium so that a flow is converted into a vortex.
 2. Thehydrogen storage system using a hydrogen storage material as defined inclaim 1, wherein the vibration unit is a piezoelectric vibrator.
 3. Thehydrogen storage system using a hydrogen storage material as defined inclaim 1, wherein the vibration unit is mounted in the heat exchangingtube.
 4. The hydrogen storage system using a hydrogen storage materialas defined in claim 1, wherein the vibration unit is mounted in a heattransfer medium chamber that allows a heat transfer medium to flowthereinto.
 5. The hydrogen storage system using a hydrogen storagematerial as defined in claim 1, wherein the vibration unit vibrates theheat exchanger by using a resonance frequency of the hydrogen storagematerial.
 6. The hydrogen storage system using a hydrogen storagematerial as defined in claim 5, wherein the vibration unit generates avibration frequency by using a resonance frequency of the hydrogenstorage material regularly or in a predetermined cycle.
 7. The hydrogenstorage system using a hydrogen storage material as defined in claim 1,wherein the heat exchanger further increases a heat exchanging volume byforming a heat exchanging pin so that the heat exchanging volume of theheat exchanging tube that makes a flow path of the heat exchangingmedium is increased and forming a groove that is obtained by modifyingthe heat exchanging tube between the pins.
 8. A hydrogen storage systemcomprising: a heat exchanger; a hydrogen storage tank comprised of ahydrogen storage alloy; and a heat transfer medium, wherein the heatexchanger includes a vibration unit.
 9. The hydrogen storage system ofclaim 8, wherein the heat transfer medium is cycled by the heatexchanger in the hydrogen storage tank.
 10. The hydrogen storage systemof claim 8, wherein the vibration unit applies vibration to the heattransfer medium so that a flow is converted into a vortex.